David White wrote: Lee read the northern papers, he knew McClellan was constantly feeling outnumbered. When your opponent believes in a fantasy that hurts him-- never, never do something to make him doubt that fantasy.
But David, if we take that argument to its logical conclusion, doesn't it mean that Lee never should have retreated at all at Sharpsburg? That he should have stayed until McClellan finally did attack him? I understand the point you make, but I just can’t agree that he made a good decision, even in light of his unquestioned mental edge over McClellan. I keep coming back to that same question - what did he have to gain by holding his ground on the 18th? And balanced against that, what did he have to lose?

It’s amazing to me that he was still there after the punishment his men took the previous day. Lee’s army was simply in no shape to fight on the 18th. They inflicted serious damage on McClellan’s army the day before, but took a 30% hit in return. When you’ve been pushed right to the brink, one-third of your army is dead or wounded, the rest are beyond exhausted, your opponent is still stronger than you, poised to renew the attack, and you’re back is against a river with only one good route of escape, it’s time to leave. Now.

Lee would have made one devil of a card player, I’ll say that. Sitting there with absolutely nothing at all in his hand, the life of his army and his new country literally on the line, and he apparently convinces McClellan that he’s holding a full house. Whatever word surpasses “gutsy,” that’s the one to describe what he did. Because if Little Mac calls his bluff, the men in his army will have to ante up their lives, and the war in the East is over.

That’s a jaw-dropping risk, especially when you can’t win the hand even if your opponent folds. Which is what McClellan did. He folded. And Lee still lost. That’s why I have a problem with his decision. It’s all downside and no upside. If what you say about Lee is the real reason why he was still there on the 18th David, then to me it means that he risked literally everything he could possibly lose on the chance that his psychological advantage over McClellan would hold. If it doesn‘t, he loses everything. If it does - he gets to retreat. It’s all risk and no reward.

I’ll say again that Lee won some truly remarkable victories in the war, and speaking to your well-considered point, David, quite often did so by running psychological rings around his opponents. With the exception of Grant, he usually forced them to dance to his tune. But in my opinion his decision to stay and offer battle again on the 18th at Antietam is simply not defensible. Lee was beyond lucky that day. So far beyond it as to nearly be out of sight.